React-Native 与 Expo：手柄硬件返回按钮

Question

By following these directions I managed to make the back button force my WebView to navigate back to the last page.

However I'm facing a side-effect: besides going back on the navigation, it also exits the App, in Android. Below is my current code. Does anyone know what is wrong with it?

function useBackButton(handler: any) {
  useEffect(()=> {
    BackHandler.addEventListener("hardwareBackPress", handler)

    return () => {
      BackHandler.removeEventListener("hardwareBackPress", handler)
    }

  }, [handler])
}


export default function App() {


  const webviewRef = useRef(null)


  function backButtonHandler() : any {
    console.log("==> Back Pressed", webviewRef.current)
    if (webviewRef) {
      if (webviewRef.current) {
        webviewRef.current.goBack()
      }
    }
  }

  useBackButton(backButtonHandler)

  return (
      <WebView 
        source={{uri: "http://my-website"}} 
        style={{ marginTop: 40 }} 
        ref={webviewRef}
        sharedCookiesEnabled
      />
  );
}

const styles = StyleSheet.create({
  container: {
    flex: 1,
    backgroundColor: '#fff',
    alignItems: 'center',
    justifyContent: 'center',
  },
});

Answer 1

As indicated by @Nadia Chibrikova, indeed there was a "return true" missing:

  function backButtonHandler() : any {
    console.log("==> Back Pressed", webviewRef.current)
    if (webviewRef) {
      if (webviewRef.current) {
        webviewRef.current.goBack()
      }
    }
    return true
  }